Antiviral Therapy

Since the discovery of HIV as the causative agent of AIDS in 1983/1984, remarkable progress has been made in finding antiretroviral drugs (ARVs) that are effective against it. A major breakthrough occurred in 1996 when it was found that triple drug therapy (HAART) could durably suppress viral replication to minimal levels. It was then widely felt, however, that HAART was too expensive and complex for low- and middle-income countries, and so, with the exception of a few of these countries, such as Brazil, a massive scale-up did not begin until the WHO launched its ‘3 by 5′ initiative and sizeable funding mechanisms, such as the Global Fund to Fight AIDS, TB and Malaria and the US President's Emergency Plan for AIDS Relief (PEPFAR), came into existence. A pivotal enabler of the scale-up was a steady lowering of drug prices through entry of generic antiretrovirals, competition between generic manufacturers and the making of volume commitments. The WHO Prequalification of Medicines Programme and the Expedited Review Provision of the US Food and Drug Administration have been important for the assurance of quality standards. Antiretroviral drug development by research-based pharmaceutical companies continues, with several important innovative products, such as long-acting agents, in the pipeline.

Active pharmaceutical ingredients (APIs) are the molecular entities that exert the therapeutic effects of medicines. This article provides an overview of the major APIs that are entered into antiretroviral therapy (ART), outlines how APIs are manufactured, and examines the regulatory and cost frameworks of manufacturing ART APIs used in low- and middle-income countries (LMICs). Almost all APIs for ART are prepared by chemical synthesis. Roughly 15 APIs account for essentially all of the ARTs used in LMICs. Nearly all of the ART APIs purchased through the Global Fund for AIDS, TB and Malaria (GFATM) or the United States President's Emergency Plan for AIDS Relief (PEPFAR) are produced by generic companies. API costs are very important because they are the largest contribution to the overall cost of ART. Efficient API production requires substantial investment in chemical manufacturing technologies and the ready availability of raw materials and energy at competitive prices. Generic API production is practiced in only a limited number of countries; the API market for ART is dominated by Indian companies. The quality of these APIs is ensured by manufacturing under good manufacturing practice (GMP), including process validation, testing against previously established specifications and the demonstration of clinical bioequivalence. The investment and personnel costs of a quality management system for GMP contribute significantly to the cost of API production. Chinese companies are the major suppliers for many advanced intermediates in API production. Improved chemistry of manufacturing, economies of scale and optimization of procurement have enabled drastic cost reductions for many ART APIs. The available capacity for global production of quality-assured APIs is likely adequate to meet forecasted demand for 2015. The increased use of ART for paediatric treatment, for second-line and salvage therapy, and the introduction of new APIs and combinations are important factors for the future of treatment in LMICs. The introduction of new fixed-dose combinations for ART and use of new drug delivery technologies could plausibly provide robust, durable ART for all patients in need, at an overall cost that is only moderately higher than what is presently being spent.

The global scale-up of antiretroviral therapy (ART) over the past decade represents one of the great public health and human rights achievements of recent times. Moving from an individualized treatment approach to a simplified and standardized public health approach has been critical to ART scale-up, simplifying both prescribing practices and supply chain management. In terms of the latter, the risk of stock-outs can be reduced and simplified prescribing practices support task shifting of care to nursing and other non-physician clinicians; this strategy is critical to increase access to ART care in settings where physicians are limited in number. In order to support such simplification, successive World Health Organization guidelines for ART in resource-limited settings have aimed to reduce the number of recommended options for first-line ART in such settings. Future drug and regimen choices for resource-limited settings will likely be guided by the same principles that have led to the recommendation of a single preferred regimen and will favour drugs that have the following characteristics: minimal risk of failure, efficacy and tolerability, robustness and forgiveness, no overlapping resistance in treatment sequencing, convenience, affordability, and compatibility with anti-TB and anti-hepatitis treatments.

A viable market for antiretroviral drugs in low- and middle-income countries is key to the continued scale-up of antiretroviral treatment. We describe the price paid by low- and middle-income countries for 10 first- and 7 second-line adult and paediatric treatment regimens from 2003 to 2012, and compare the price of their finished formulations with the price of their active pharmaceutical ingredients in 2005, 2007, 2010 and 2012. Between 2003 and 2012 the median price of adult first-line treatment regimens per treatment-year decreased from USD499 to USD122, and that of second-line regimens from USD2,934 to USD497. In 2005 adult formulations were sold for a price 170% higher than the cost of their active pharmaceutical ingredients. This margin had decreased to 28% in 2012. Between 2004 and 2013, the price of paediatric treatment per treatment-year decreased from USD585 to USD147 for first-line and from USD763 to USD288 for second-line treatment. In 2005, paediatric treatment regimens were sold at a price 231% higher than the cost of their active pharmaceutical ingredients. This margin remained high and was 195% in 2012. The prices paid for antiretroviral drugs by low- and middle-income countries decreased between 2003 and 2012. Although the margins on their sale decreased, there is likely still space for price reduction, especially for the more recent World Health Organization recommended adult first-line regimens and for paediatric treatment.

This review outlines the main issues concerning the production of antiretroviral (ARV) drugs in middle- and low-income countries and the relevant political, legal and technical requirements for supporting such production. The requirements for efficient local production, including the manufacture of generic and branded products and public demand, have been considered from economic, market and socio-political perspectives. A steady and consistent government policy is crucial to success. Additional crucial factors in establishing local production are adequate infrastructure, qualified human resources in technical and managerial areas, and production–distribution logistics systems. The creation or strengthening of a national drug regulatory agency is a basic requirement. Production of ARVs relies on the structure of the international market for active pharmaceutical ingredients (APIs), which are highly monopolized for inclusion in branded or patented drugs, or are concentrated in a few Asian generic companies. Countries seeking to begin local production must develop strategies to overcome the various barriers. For instance, sub-Saharan African countries may benefit from developing multilateral health agreements with neighbouring countries. Such agreements are recommended and should be complemented by technology transfers, especially for the manufacture of APIs. Achieving a production level that is sustainable in the long term is crucial to maintaining patients’ access to ARVs.

The number of patients receiving antiretroviral therapy (ART) has increased from around half a million in 2003 to almost 10 million in only 10 years, and will continue to increase in the coming years. Over 16 million more are eligible to start ART according to the last World Health Organization (WHO) guidelines. The demand is also switching from the less expensive antiretrovirals (ARVs) that allowed such scale-up to newer more expensive ones with fewer side effects or those that can be used by people who have developed resistance to first-line treatment. However, patents on these new drugs can delay robust generic competition and, consequently, price reduction made possible by economies of scale. Various ways to address this issue have been envisaged or implemented, including the use of the flexibilities available under the Agreement on Trade-Related Aspects of Intellectual Property Rights (TRIPS), systematic widespread voluntary licensing, of which the Medicines Patent Pool (MPP) is an example, and the application of different prices in different countries, called tiered pricing. This paper helps explain the impact of patents on market competition for ARVs and analyses various approaches available today to minimize this impact.

Medicines of uncertain quality, safety and efficacy can be worse than no treatment at all. It is the responsibility of national medicines regulatory authorities to protect patients from harm. Yet, there are great disparities in regulatory capacity globally, preventing large populations from accessing the benefits of advances in the pharmaceutical field. This article describes the main regulatory functions and how they are applied to assure the quality, safety and efficacy of different types of medicines in different environments. It gives examples of initiatives that have increased access to good quality medicines worldwide and – more importantly – are laying the groundwork for collaborative approaches aiming to ensure that pharmaceutical products meet the same, stringent quality standards in all parts of the world.

Procurement, the country-level process of ordering antiretrovirals (ARVs), and supply chain management, the mechanism by which they are delivered to healthcare facilities, are critical processes required to move ARVs from manufacturers to patients. To provide a glimpse into the ARV procurement and supply chain, the following pages provide an overview of the primary stakeholders, principal operating models, and policies and regulations involved in ARV procurement. Also presented are key challenges that need to be addressed to ensure that the supply chain is not a barrier to the goal of universal coverage. This article will cover the steps necessary to order and distribute ARVs, including different models of delivery, key stakeholders involved, strategic considerations that vary depending on context and policies affecting them. The single drug examples given illustrate the complications inherent in fragmented supply and demand-driven models of procurement and supply chain management, and suggest tools for navigating these hurdles that will ultimately result in more secure and reliable ARV provision. Understanding the dynamics of ARV supply chain is important for the global health community, both to ensure full and efficient treatment of persons living with HIV as well as to inform the supply chain decisions for other public health products.

Haiti is the poorest country in the Western Hemisphere and has the highest number of people living with HIV in the Caribbean, the region most impacted by HIV outside of Africa. Despite continuous political, socioeconomic and natural catastrophes, Haiti has mounted a very successful response to the HIV epidemic. Prevention and treatment strategies implemented by the government in collaboration with non-governmental organizations have been instrumental in decreasing the national HIV prevalence from a high of 6.2% in 1993 to 2.2% in 2012. We describe the history and epidemiology of HIV in Haiti and the expansion of antiretroviral therapy (ART) over the past decade, with the achievement of universal access to ART for patients meeting the 2010 World Health Organization guidelines. We also describe effective models of care, successes and challenges of international funding, and current challenges in the provision of ART. We are optimistic that the goal of providing ART for all in need remains in reach.

Public sector antiretroviral provision had a slow start in South Africa despite a raging epidemic and a World AIDS conference that shed significant public light on the disparities of therapy access globally. This was largely due to political prevarication in the midst of AIDS denialism. There has been an unprecedented expansion in the HIV treatment programme since 2008. As a result, South Africa now has the largest number of patients on antiretroviral drugs in the world, and South African life expectancy has increased by more than a decade. However, this has led to a number of fiscal, logistic and operational challenges that the country must face as the treatment programme continues to expand. Challenges include increasing detection within communities, linkage and retention in care, while strengthening operational support functions such as consistent drug supply, health staffing and infrastructure, diagnostic services, programme monitoring and sustainable financing. As a middle-income country, albeit with marked income inequality, and the heaviest HIV burden in the world, South Africa is a test case of whether a large-scale public health programme can boast of success in the face of numerous other health-system challenges.

The number of people living with HIV (PLHIV) continues to increase around the world because of the increasing number on antiretroviral therapy (ART) and their associated increase of life expectancy, in addition to the number of people newly infected with HIV each year. Unless a ‘cure’ can be found for HIV infection, PLHIV can anticipate the need to take antiretroviral drugs (ARVs) for the rest of their lives. Because ARVs are now being used for HIV prevention, as well as for therapeutic purposes, the need for effective, affordable ARVs with few adverse effects will continue to rise. It is important to note that the dramatic growth in treatment coverage of PLHIV seen during the past decade has been primarily due to the increased use of generic ARVs. Thus, there will be a need to scale-up the research and development, production, distribution and access to generic ARVs and ART regimens. However, these processes must occur within national and international regulated free-market economic systems and must deal with increasingly multifaceted patent issues affecting the price while ensuring the quality of the ARVs. National and international regulatory mechanisms will have to evolve, which will affect broader national and international economic and trade issues. Because of the complexity of these issues, the Editors of this Supplement conceived of asking experts in their fields to describe the various steps from relevant research and development, to production of generic ARVs, their delivery to countries and subsequently to PLHIV in low- and middle-income countries. A main objective was to highlight how these steps are interrelated, how the production and delivery of these drugs to PLHIV in resource-limited countries can be made more effective and efficient, and what the lessons are for the production and delivery of a broader set of drugs to people in low- and middle-income countries.